Ruh huh! Sniffer dogs could be used for the early detection of lung cancer, German scientists show.

Still the most common cause of death from cancer worldwide, lung cancer isn’t strongly associated with any symptoms, and early detection is usually by chance.

Oftentimes, the presence of cancer is linked to volatile organic compounds (VOCs) produced by tumors. However, no lung cancer-specific VOCs have ever been identified because patients aren't allowed to eat or smoke before the test, analyses take a long time, and the risk of interference is high.

So a team led by Thorsten Walles of Schillerhoehe Hospital wanted to see if trained sniffer dogs could identify a VOC in the breath of patients.

“This is a big step forward in the diagnosis of lung cancer, but we still need to precisely identify the compounds observed in the exhaled breath of patients,” Walles says. “It is unfortunate that dogs cannot communicate the biochemistry of the scent of cancer!”

Once they figure out the chemical the dogs are detecting, researchers can develop a screening method. Some are already working on ‘electronic noses’ that would be able to detect the same chemical as dogs.